With rapid development of mobile communication technologies, data services such as wireless network access get mature, and portable and small terminal equipments for wireless network access, such as, wireless data cards, attract more and more attention and get more and more popular. Wireless data cards do not need to be charged by a power supply, and can be directly inserted onto a universal serial bus (USB) port on a notebook computer or a desktop computer for being powered. The user only needs a subscriber identity module (SIM) card for data services through wireless internet access without the need of a network cable, and can enjoy the fun of Internet surfing anytime and anywhere.
The currently used data card requires the user to input a password, and after passing through authentication, the data card can be used.
However, the current data cards has disadvantages in terms of security, because the password input by the user is generally numerals, which can be easily cracked and has low security.